Abstract: Provided is a magnetic carrier satisfying leakage, white spots, charging property and high developing performance in a low electric field and having excellent durability. The magnetic carrier is a magnetic carrier comprising a magnetic substance-dispersed resin carrier core containing a magnetic substance and a binder resin, and a coating resin on a surface thereof, wherein the magnetic substance comprises a magnetic substance A having a shape without vertexes and a magnetic substance B having a shape with vertexes, the magnetic substance B has a number average particle diameter of 0.40-2.00 ?m, and in a reflection electron image of a section of the magnetic substance-dispersed resin carrier core taken by a scanning electron microscope, an area proportion of the magnetic substance B is larger than an area proportion of the magnetic substance A within a region from the surface of the magnetic substance-dispersed resin carrier core to a depth of 1.0 ?m.

Abstract: A carrier for a two-component developer includes magnetic particles, and a resin coating layer that covers the magnetic particles. The resin coating layer contains metal boride particles having a volume average primary particle diameter of from about 300 nm to about 2,500 nm.

Abstract: A carrier for developing an electrostatic charge image includes a core containing a magnetic material and a coating layer, in which the coating layer includes porous carbon having a volume average particle size of from 0.5 ?m to 2 ?m and a BET specific surface area of from 1 m2/g to 5 m2/g, and a resin.

Abstract: A two-component developer includes: a toner; a carrier having a surface energy of from about 23 dyne/cm to about 37 dyne/cm; and an external additive having a shape factor SF1 of from about 130 to about 150 and a number-average particle diameter of from about 80 nm to about 1 ?m; and an existence ratio A of the external additive on a surface of the toner and an existence ratio B of the external additive on a surface of the carrier satisfying the relationship of the following Expression 1: 0.04?B/A?0.4.

Abstract: A carrier for electrostatic latent image developing is composed of carrier core containing a binder resin and magnetic material particles, and a shell layer that covers the carrier core. The binder has an acid value of at least a predetermined value, and contains a resin having a carboxyl group. The shell layer is composed of a resin selected from melamine resin and urea resin.

Abstract: An object of the present invention is to provide a carrier containing core material particles having magnetism and a coating layer on the surfaces of the core material particles, wherein the core material particles have a magnetization at a magnetic field of 1,000 Oersted of 40 emu/g to 100 emu/g, and the carrier has a weight average particle diameter of 20 ?m to 45 ?m, a resistance (Log R) of 11 ?·cm to 17 ?·cm and a relaxation time ? of 150 seconds to 800 seconds.

Abstract: The present invention relates to a magnetic carrier for an electrophotographic developer comprising spherical composite particles comprising spherical composite core particles comprising at least ferromagnetic iron oxide fine particles and a cured phenol resin and having an average particle diameter of 1 to 100 ?m, and a melamine resin coating layer formed on the respective core particles, wherein a ratio of R100 to R300 (R100/R300) in which R100 is an electric resistance value as measured when applying a voltage of 100 V to the magnetic carrier; and R300 is an electric resistance value as measured when applying a voltage of 300 V to the magnetic carrier, is controlled to lie within the range of 1 to 50.

Abstract: The present invention provides a magnetic carrier for an electrophotographic developer which has an excellent durability and a stable charging property and is free from occurrence of spent toner thereonto, and a two-component system developer comprising the magnetic carrier for an electrophotographic developer and a toner. The present invention relates to a core material of a magnetic carrier for an electrophotographic developer comprising spherical composite particles comprising at least ferromagnetic iron oxide fine particles and a cured phenol resin and having an average particle diameter of 1 to 100 ?m, a resin index of the spherical composite particles being within the range of 35 to 80%, and a magnetic carrier obtained by coating a surface of respective particles of the magnetic carrier core material with a resin.

Abstract: A latent electrostatic image developing carrier including: core particles each having magnetism; and a coating layer covering each of the core particles, wherein the latent electrostatic image developing carrier has a shape factor SF-2 of 115 to 150 and has a bulk density of 1.8 g/cm3 to 2.4 g/cm3, wherein the core particles have a shape factor SF-2 of 120 to 160 and have an arithmetic mean surface roughness Ra of 0.5 ?m to 1.0 ?m, and wherein the coating layer contains a resin and a filler and an amount of the filler contained in the coating layer is 50 parts by mass to 500 parts by mass per 100 parts by mass of the resin contained in the coating layer.

Abstract: A carrier including a magnetic core particle and a resin layer covering a surface of the magnetic core particle. The magnetic core particle is a ferrite particle including strontium in an amount of 0.005 to 3% by mass, measured by fluorescent X-ray spectroscopy. The resin layer comprises a resin obtained by heating a copolymer comprising a silicon-containing unit A and another silicon-containing specific unit B.

Abstract: A contact developing method including supplying a two-component developer to an electrostatic latent image on a rotating image bearing member by rotating a developing sleeve and a rotatable magnet having multiple magnetic poles provided inside the developing sleeve, to develop the electrostatic latent image into a toner image. The developing sleeve and the image bearing member rotate in the same direction while facing each other. The two-component developer comprises a non-magnetic toner and a carrier. The carrier comprises a magnetic core particle and a resin layer covering the magnetic core particle. The resin layer comprises a conductive particle and a resin. The conductive particle comprises an alumina-based material and a conductive layer covering the alumina-based material. The resin is obtained by heating a copolymer comprising a monomer A unit and a monomer B unit.

Abstract: The present invention provides a carrier for replenishment including an associated particle in which single particles each having a core material and a resin layer covering the core material, are bound via the resin layer, the carrier being used in a developer for replenishment of a trickle development system, and the system including performing development while the developer for replenishment is replenished, upon development of a latent image on a latent image holding member using a development unit.

Abstract: An electrostatic image developing carrier includes a ferrite particle and a resin layer that coats the ferrite particle, wherein a magnesium element content of the ferrite particle is from about 3.0% by weight to about 20.0% by weight; wherein a manganese element content of the ferrite particle is from about 0.2% by weight to about 0.8% by weight; and wherein a content of toluene is more than about 100 ppm and not more than about 2,000 ppm.

Abstract: An anisotropic magnetic material-dispersed resin carrier including: fine magnetic particles; and a binder resin in which at least the fine magnetic particles are dispersed, wherein the anisotropic magnetic material-dispersed resin carrier has a magnetic anisotropy where magnetic fields of the fine magnetic particles are orientated in the same direction, and wherein the anisotropic magnetic material-dispersed resin carrier has a saturation magnetization of 16 emu/g to 30 emu/g, a coercive force of 15 kA/m to 40 kA/m, and a number average particle diameter of 15 ?m or more but less than 100 ?m.

Abstract: A method of producing a carrier for electrophotography includes: covering a surface of a core particle with a coating layer including resin particles and a crosslinking resin in an uncrosslinked state present in spaces between the resin particles; and applying a mechanical impact from the outer surface of the coating layer before crosslinking of the crosslinking resin.

Abstract: The invention provides a developer for developing an electrostatic latent image, the developer having at least: a transparent toner; and a carrier. The carrier contains at least: a magnetic particle; and a resin coating layer. The resin coating layer coats the surface of the magnetic particle and has cyan color. The invention further provides a developer cartridge storing the developer. The invention further provides a process cartridge storing the developer. The invention further provides an image formation apparatus having at least a color toner image-forming unit, a transparent toner image-forming unit that uses the developer to form a transparent toner image, and a fixing unit.

Abstract: A carrier for developing an electrostatic latent image includes carrier particles, and the carrier particles include magnetic particles and a coating layer coating the surfaces of the magnetic particles. The BET specific surface area of the magnetic particles is 0.1300 m2/g to 0.2500 m2/g, and the difference in BET specific surface areas obtained by subtracting the BET specific surface area of the magnetic particles from the BET specific surface area of the carrier particles is 0.0300 m2/g to 0.400 m2/g.

Abstract: An electrostatic image developing carrier includes a core particle and a coating layer on the core particle. The coating layer contains a resin having a crosslinked structure formed by using at least one compound selected from boric acid and boric acid derivatives.

Abstract: An electrostatic charge image developing carrier includes a core particle and a coating layer with which the surface of the core particle is coated. The coating layer includes an acrylic resin having a constituent unit in which a silicone chain is disposed in a branch.

Abstract: An electrostatic image developing carrier includes a ferrite particle that contains magnesium element in an amount of about 3.0 wt % or more and about 10.0 wt % or less and manganese element in an amount of about 0.2 wt % or more and less than about. 1.0 wt %; and a resin layer that covers the ferrite particle.

Abstract: An electrostatic image developing toner includes toner particles that contain a binding resin, a coloring agent and a release agent and that have D50 of from about 2.0 ?m to about 8.0 ?m, D50 standing for a volume-average particle size of the toner particles; and non-colored release agent particles, wherein out of the non-colored release agent particles, those ranging in volume-average particle size of from about 0.8 to about 1.2 times a value of D50 are present in a proportion of about 50 or below per 5,000 of the toner particles.

Abstract: A carrier for developing an electrostatic charge image includes a core containing a magnetic material and a coating layer, in which the coating layer includes porous carbon having a volume average particle size of from 0.5 ?m to 2 ?m and a BET specific surface area of from 1 m2/g to 5 m2/g, and a resin.

Abstract: A carrier for developing electrostatic latent image, including a particulate magnetic core material; and a coated layer covering the surface of the particulate magnetic core material, wherein the coated layer includes a resin including a silicone resin and a methacrylic ester or an acrylic ester resin, and a filler including a substrate; and an electroconductive layer comprising tin dioxide (SnO2), overlying the substrate, and wherein the carrier includes tin (Sn) in an amount not less than 0.5% by atom and has a ratio (Sn/Si) of tin (Sn) to silicon (Si) of from 0.03 to 0.2 when subjected to an XPS analysis.

Abstract: There are provided a resin-coated carrier for an electrophotographic developer, in which a magnetic particle is coated with a resin on its surface, and the coating resin contains a carbon nanotube having a carbon content of 75% by weight or more, and an electrophotographic developer using the resin-coated carrier.

Abstract: The carrier is used for a two-component developer for developing an electrostatic latent image, and includes a particulate magnetic core material; and a cover layer located on a surface of the particulate magnetic core material and including a crosslinked material. The crosslinked material is formed by hydrolyzing a copolymer including at least a unit (A) having a specific acrylic siloxane structure including a tris(trialkylsiloxy)silanyl group and a unit (B) having a specific acrylic silicone structure to form a material having a silanol group, and subjecting the material having a silanol group to a condensation reaction using an organic zirconium-containing catalyst.

Abstract: A latent electrostatic image developing carrier including a carrier core material, and a coating layer containing a resin and provided on a surface of the carrier core material, wherein the coating layer includes a particulate material containing at least first fine conductive particles and second fine conductive particles, and wherein the first fine conductive particles and the second fine conductive particles satisfy the relationships expressed by Expressions 1 and 2, 3?D1/D2?15 . . . Expression 1, where D1 denotes a dispersed particle diameter of the first fine conductive particles and D2 denotes a dispersed particle diameter of the second fine conductive particles, and ?7E?R1×R2?8E . . . Expression 2, where R1 denotes a powder specific resistance of the first fine conductive particles and R2 denotes a powder specific resistance of the second fine conductive particles.

Abstract: An electrostatic image developing carrier including at least a core material and a coating resin layer which coats the surface of the core material, the resin layer comprising a thermoplastic resin having an alicyclic group, a thermal reduction in accordance with the TGA method being in the range of 0.5 weight % to 5 weight % of the whole of the carrier in the range of 100° C. to 400° C., and further an endothermic quantity of the whole of the carrier in accordance with the DTA method is in the range of 7 mJ/g to 40 mJ/g in the range of 100° C. to 400° C.

Abstract: A carrier comprising a magnetic core particle having a shape factor SF-2 of 130 to 160 and a resin layer covering a surface of the magnetic core particle. The resin layer comprises a conductive particle and a resin obtained by heating a copolymer comprising a silicon-containing A unit and another silicon-containing B unit.

Abstract: The invention provides an electrophotographic toner having a crystalline polyester resin; a non-crystalline polyester resin; a colorant; and a releasing agent. A resin (i), that is included in a toluene-soluble component of the toner and having a molecular weight of 30,000 to 100,000 as measured by gel permeation chromatography relative to polystyrene standards, has an acid value A. A resin (ii), that is included in a toluene-soluble component of the toner and having a molecular weight of 8,000 to 12,000 as measured by gel permeation chromatography relative to polystyrene standards, has an acid value B. A resin (iii), that is included in a toluene-insoluble component of the toner, has an acid value C. The acid values A, B, and C satisfy the inequation of B>A>C. The invention further provides an electrophotographic developer using the toner, a toner cartridge storing the toner, and an image forming method using the developer.

Abstract: An electrostatic charge image developing carrier has magnetic particles and a coating resin layer that coats surfaces of the magnetic particles and contains a hindered amine compound.

Abstract: A two-component developer is disclosed, composing a toner comprising parent toner particles with an attached external additive and a carrier provided with a resin covering layer on a surface of a core particle, wherein the resin covering layer comprises a binder resin comprising an acrylic resin and when the resin covering layer is divided in half to a core particle side and a surface side, a nitrogen element content of the core particle side is larger than a nitrogen element content of the surface side.

Abstract: The invention provides a toner for developing an electrostatic image including toner particles having a shape factor SF1 of 110 or more and including a binder resin, and particles of an external additive that adhere to the toner particles, wherein the particles of the external additive including first particles, and second particles which are adhered to the first particles and have a primary particle size of 0.2 times to 0.5 times as large as that of the first particles, and in an image obtained by observing the particles of the external additive with a microscope, when the projection surface area of the first particle is defined as S1 and the total of the projection surface areas of the second particles which are not hidden by the first particle is defined as S2, S2 being from 0.1 times to 0.5 times as large as S1.

Abstract: An electrostatic latent image developing toner includes a mother particle which contains a coloring agent, a release agent and a binder resin; and an inorganic particle which is added to the surface of the mother particle, and wherein a relation between a relaxation time t and a relaxation modulus G(t) which are determined from the dynamic viscoelasticity measurement made on the toner satisfies the following equations (1) and (2); G(t1)<100 Pa??(1) 515<(G(t2)?G(t1))/(log(t1)?log(t2))<1,230??(2) wherein t1 represents the maximum relaxation time and t2 represents the minimum relaxation time.

Abstract: Provided is a magnetic carrier satisfactory in terms of the suppression of leakage and solid carrier adhesion, charge-providing performance, and developability. The magnetic carrier is a magnetic carrier, including filled core particles of which pores of porous magnetic core particles are filled with a filling resin composition, and having a surface coated with a coating resin composition, in which the coating resin composition comprises a coating resin and a carbon black, an amount of the coating resin composition is 2.0 parts by mass or more and 5.0 parts by mass or less with respect to 100.0 parts by mass of the filled core particles; and a particle diameter of the carbon black in the coating resin composition Pv at a maximum frequency in a particle size distribution based on a volume of the carbon black is 1.0 ?m or more and 10.0 ?m or less.

Abstract: A carrier for developing an electrostatic charge image, including a core, and a coating layer including a resin and inorganic oxide particles that exhibit electroconductivity, by which the core is coated, wherein the inorganic oxide particles have, when they are aggregated, an aggregation size of, or when they are not aggregated, a primary particle size of, from 230 nm to 970 nm.

Abstract: A carrier, including a magnetic particulate core material and a resin layer on the core material, wherein the resin layer includes a resin obtained by heat treatment of a copolymer including a site derived from a monomer component having the following formula (1) and a site derived from a monomer component having the following formula (2), and includes a cross-linked material obtained by hydrolysis of the copolymer to produce a silanol group and condensation using an organotitanium compound: wherein R1 represents a hydrogen atom or a methyl group; m represents an alkylene group having 1 to 8 carbon atoms; R2 represents an alkyl group having 1 to 4 carbon atoms; R3 represents an alkyl group having 1 to 8 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms; X represents 10 to 90 mol %; and Y represents 10 to 90 mol %.

Abstract: The carrier is used for a two-component developer for developing an electrostatic latent image, and includes a particulate magnetic core material; and a cover layer located on a surface of the core material and including a crosslinked material and barium sulfate. The cover layer is formed by applying a coating medium including barium sulfate, a copolymer including a unit (A) having a specific acrylic siloxane structure including a tris(trialkylsiloxy)silanyl group and a unit (B) having a specific acrylic silicone structure having a crosslinking ability, and a condensation reaction catalyst, heating the applied medium to a temperature of from 100° C. to 230° C. so that the copolymer is hydrolyzed to produce a material having a silanol group, and the material and the catalyst are subjected to a condensation reaction to form the crosslinked material.

Abstract: A hybrid developing carrier, comprising a resin layer formed on an outermost surface, wherein the surface of said resin layer is provided with sites formed of an inorganic compound having basic points or acidic points and sites where the resin forming the resin layer is exposed, a hybrid developing device equipped with the hybrid developing carrier, and an image-forming apparatus equipped with the hybrid developing device.

Abstract: An electrophotographic developer is provided which includes: a toner that includes toner base particles and an external additive attached to a surface of the toner base particles and has an amount of Al on the surface of the toner base particles of from about 0.002 to about 0.02 atm %; and a carrier that includes magnetic particles and a coating resin layer that coats the magnetic particles, the coating resin layer including particles with a volume-average particle diameter of from about 80 to about 800 nm, such as organic particles or inorganic particles having an organic layer on a surface of the inorganic particles, the carrier satisfying any one of the following formulas, where SP1, SP2 and SP3 represent a solubility parameter of resin of the coating resin layer, the organic particles, and the organic layer respectively: about 10>|SP1?SP2|>about 4??(1); and about 10>|SP1?SP3|>about 4??(2).

Abstract: The present invention provides a carrier which includes core material particles, and a coating layer on surfaces of the core material particles, wherein the coating layer contains a crosslinked product which is obtained by condensation of a silicone resin with an organic zirconium catalyst, the silicone resin having at least one of a silanol group and a functional group capable of generating a silanol group by means of hydrolysis.

Abstract: A latent electrostatic image developing carrier including: core particles each having magnetism; and a coating layer covering each of the core particles, wherein the latent electrostatic image developing carrier has a shape factor SF-2 of 115 to 150 and has a bulk density of 1.8 g/cm3 to 2.4 g/cm3, wherein the core particles have a shape factor SF-2 of 120 to 160 and have an arithmetic mean surface roughness Ra of 0.5 ?m to 1.0 ?m, and wherein the coating layer contains a resin and a filler and an amount of the filler contained in the coating layer is 50 parts by mass to 500 parts by mass per 100 parts by mass of the resin contained in the coating layer.

Abstract: The present disclosure provides carriers for use with toner compositions. In embodiments, a carrier may include a core, having a dry powder polymer coating. The polymer coating possesses a carbon to oxygen from about 3:1 to about 8:1. In embodiments, the coating may also include a colorant, such as carbon black. Processes for coating such carriers with the dry powder polymer coatings are also provided.

Abstract: An electrophotographic carrier includes a magnetic core material and a resin layer that coats the magnetic core material, the resin layer comprising a resistance control agent and a polymer including a repeating unit derived from an alicyclic group-containing methacrylic ester, the resin layer including a monomer as a base material of the repeating unit in the polymer in an amount of from about 0.5% by weight to about 3.0% by weight relative to the total amount of the resin layer.

Abstract: A carrier for a two-component developer includes magnetic particles, and a resin coating layer that covers the magnetic particles. The resin coating layer contains metal boride particles having a volume average primary particle diameter of from about 300 nm to about 2,500 nm.

Abstract: The present disclosure provides carriers for use with toner compositions. In embodiments, a carrier may include a core, having a dry powder polymer coating. In embodiments, the coating may also include a colorant, such as carbon black. Processes for coating such carriers with the dry powder polymer coatings are also provided.

Abstract: There is provided a method for producing a carrier, which includes depositing a resin coating layer on the surface of a magnetic material; adding a treatment agent for a conductor precursor to the resin coating layer so as to treat the resin coating layer with the treatment agent; and exposing the treatment agent-added resin coating layer to a conductor precursor in a supercritical or subcritical fluid so as to form a conductor in the resin coating layer.

Abstract: An electrostatic charge image development carrier includes magnetic core particles and a resin coating layer that contains titanium dioxide particles doped with niobium and coats each of the magnetic core particles.

Abstract: The present disclosure provides carriers for use with toner compositions. In embodiments, a carrier may include a core, having a dry powder polymer coating. In embodiments, the coating may also include a colorant, such as carbon black. Processes for coating such carriers with the dry powder polymer coatings are also provided.

Abstract: In a method for coating electrophotographic carrier core surfaces with a resin composition by rotating a rotator having a plurality of agitating blades on its surface in a casing; a coating treatment material that is introduced to a space defined between the rotator and the casing is in a packing of from 50% to 98% by volume; at the time of coating treatment, the electrophotographic carrier core surfaces are coat-treated with the resin composition while being put forward and put backward; and the electrophotographic carrier cores and the resin composition are, at the time of coating treatment, temperature-controlled at a specific temperature T (° C.) or below. This method enables the electrophotographic carrier core surfaces to be more uniformly coated with a coating resin.

Abstract: An electrostatic image developing carrier includes a ferrite particle that contains magnesium element in an amount of about 3.0 wt % or more and about 10.0 wt % or less and manganese element in an amount of about 0.2 wt % or more and less than about 1.0 wt %; and a resin layer that covers the ferrite particle.